论文标题:冲击式水轮机电站系统水力过渡过程研究
Study on the Transient Process of Power Station by Impulse Turbine
论文作者 陈丹
论文导师 杨建东,论文学位 硕士,论文专业 水利水电工程
论文单位 武汉大学,点击次数 144,论文页数 88页File Size2624k
2004-05-01论文网 http://www.lw23.com/lunwen_25455602/ 冲击式水轮机,过渡过程,折向器,喷嘴,上游调压室
impulse turbine;transient;deflector;jet;upper tank
随着水电事业的迅速发展，国内外已建和待建的水电站中有不少是高水头、小流量、长引水道的系统，如布德朗水电站、四方洞水电站、白水河二级水电站、麻线坪水电站等，这类电站由于水头范围以及气蚀和磨损等条件的限制，通常选用冲击式水轮机。这种机型以其特有的结构与工作特性，对水电站系统的过渡过程带来了一定的影响，本文在已成熟的混流式水轮机水力过渡过程数值仿真计算的理论基础上，通过修改边界条件、机组方程、调速器方程等，提出了专门针对冲击式水轮机水力过渡过程计算的一套理论及方法，其主要内容如下： 第一章，指出本文研究的意义和目的，回顾前人对水力过渡过程、冲击式水轮机，以及上游调压室设置条件的研究成果，在此基础上提出本文的研究内容。 第二章，提出水电站水力过渡过程的计算原理及方法，并列举了整个系统中的各种边界条件及其处理。 第三章，从折向器动作的物理本质和冲击式水轮机特性曲线入手，推导出了折向器方程；分别针对单喷嘴和多喷嘴冲击式水轮机，提出了依据出力求解和依据转矩求解两种大波动过渡过程的计算理论，并通过工程实例得以验证。 第四章，在大波动过渡过程计算理论的基础上，引入调速器方程及机组运动方程，形成小波动计算理论。并通过工程实例，对折向器在小波动过渡过程中的影响、喷嘴如何随负荷变化而切换等问题作了分析与探讨。 第五章，以前面章节论证的冲击式水轮机过渡过程计算理论为基础，针对麻线坪电站实例，从大波动调保参数计算、小波动稳定性分析以及参与调频水力干扰计算三方面出发，分析论证了调压井在该类高水头长引水道电站中的作用。 第六章，总结全文，提出今后研究的重点和方向。
With the rapid development of hydropower projects, there are lots of power stations built or to be built with the properties of high-head, low-discharge and long-conduit systems, such as Bradley, Sifangdong, Baishuihe secondary and Maxianpin power station etc. This kind of stations usually adopts water impulse turbines because of the limitations of water head, cavitation and friction. But owing to their special structures and running characteristics, impulse turbines usually bring special effects to hydraulic transients. So it is very significant to research the mechanisms on how the impulse turbines function during the transient process. This thesis will present a set of new theories and methods, mainly by establishing the equations of boundary, unit and governor, to give a solution on simulating the transient process by impulse turbines, which is also based on the mature simulation methodology for transient process by mixed-flow-turbines. The major contents are listed as follows:Chapter 1: Indicate the significance and objective of this paper, review the previous achievements of the transient process, impulse turbine and upper tank, and then present the study purpose of this paper.Chapter 2: Present the basic simulation methodology of transient flow and list all kinds of boundary conditions in the objective systems.Chapter 3: From the physical essences of deflector motions and the characteristic curves of impulse turbine, give the detailed deduction on new deflector formulas. And then, aiming at single-jet and multiple-jet impulse turbine models respectively, describe two sets of methods for large-wave-transient process, which can be verified by a practical example illustrated at the end of the chapter.Chapter 4: On the foundation of large-wave-transient theories, establish the theories for small-wave-transients by importing governor and unit motions equations. And then, through a practical example, give the discussions on the problems such as the influences on the small-wave-transients by deflector motions and how to adjust to jet numbers corresponding to the load changes etc.Chapter 5: Based on the previous fruits of this thesis and taking Maxianpin station as an example, demonstrate the functions of upper tanks in this kind of high-head and long-conduit stations by analyzing the calculation results of large-wave-transients, small-wave-transients and hydraulic perturbation.Chapter 6: Summarize the whole paper, and present the future research directions and emphasis.
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